Automatic choke adjusting means



May 7, 1963 R. M. SAXBY AUTOMATIC CHOKE ADJUSTING MEANS 2 Sheets-Sheet 1 Filed May 18, 1959 INVENTOR. R M. SAXBY May 7, 1963 R. M. SAXBY AUTOMATIC CHOKE ADJUSTING MEANS 2 Sheets-Sheet 2 Filed May 18, 1959 INVENTOR. RI GHARD M. SAXBY United States Patent 3,088,320 AUTOMATIC CHOKE ADJUSTING MEANS Richard M. Saxby, Detroit, Mich, assignor to Holley Carburetor Company, Van Dyke, Mich, a corporation of Michigan Filed May 18, 1959, Ser. No. 814,058 4 Claims. (Cl. 73--363.5)

The present invention relates to automatic choke adjusting means, and more particularly, to adjustable thermostat mechanism including improved adjusting means therefor.

It is an object of the present invention to provide adjustment means for an automatic choke accessible when the automatic choke mechanism is fully assembled.

It is a further object of the present invention to provide a thermostat, preferably a bimetal thermostat, having an actuator connected thereto, in combination with means for adjusting the effectiveness of said thermostat.

More specifically, it is an object of the present invention to provide a temperature responsive mechanism for effecting adjustment of an automatic choke comprising a housing and a removable cover plate on which is mounted a temperature responsive thermostat, and means for adjusting the effectiveness of said thermostat.

More specifically, it is an object of the present invention to provide mechanism as described in the preceding paragraph in which the thermostat is a coiled bimetal thermostat having one end secured to a rotatably adjustable post, and in which the means for adjusting the effectiveness of the thermostat comprises a rotatable member having a portion extending to the inner side of said cover plate and connected to said post, and a portion extending to the outside of said cover plate for providing for adjustment of said post when said cover plate is in position.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings, illustrating preferred embodiments of the invention, wherein:

FIGURE 1 is a fragmentary elevational view showing the association between a carburetor having an automatic choke and temperature responsive means for adjusting said choke.

FIGURE 2 is a fragmentary side elevational view of the temperature responsive adjustment means with parts broken away.

FIGURE 3 is an exploded view of the elements of the temperature responsive adjusting means.

FIGURE 4 is a view similar to FIGURE 2 showing a specifically difierent embodiment of the present invention.

FIGURE 5 is an exploded view similar to FIGURE 3, showing the components of the device illustrated in FIG- URE 4.

As best seen in FIGURE 1, the present invention relates to automatic control of the choke of a carburetor 12 provided in association with an internal combustion engine. Specifically, the carburetor is shown as mounted on the intake manifold 14 of an internal combustion engine. The intake manifold is provided with a recess as suggested by the dotted lines at 16, which is adapted to receive a temperature responsive element as will subsequently be described. The recess 16 constitutes a housing having a relatively large opening adapted to be closed by a removable cover plate 18 as will subsequently be described. A temperature responsive thermostat is received in the housing and is connected to an actuator 20 which extends through an opening in the housing cover plate and is adapted to be connected to a lever 22 fixed to the shaft 24 of the choke 10. Longitudinal movement of the actuator 20 controls the position of the choke.

Referring now to FIGURES 2 and 3 the cover plate 18 has fixed thereto in depending relation a bracket 28 to which is secured a rotatable post 30' having an elongated slot 32 for receiving one end of a coiled bimetal thermostat 34. The post 30 has fixedly secured thereon a disc or sector 36 having teeth formed at its periphery. The reduced end portion 38 of the post extends through an opening in the bracket 28 and is retained in position thereon by an E-ring 40.

Associated with the post 30 is a thermostat lever 42 of U-shaped cross-section having legs 43 and 44 between which the coiled bimetal thermostat is received. The post 30 extends through openings in the legs 43 and 44 and receives the inner end of the coiled bimetal thermostat. The post, thermostat, and lever are retained in assembled position by a hairpin retainer 46 having legs received in an annular groove 48 formed adjacent one end of the post 30. A washer 49 is received between retainer 46 and leg 43.

The lever 42 adjacent its closed end is provided with a pair of aligned openings which receive a laterally bent portion 59 of the actuator link or rod 20, the upper end of which is secured to the lever 22 previously referred to. The outer end of the bimetal coil is looped as indicated at 52 to engage the laterally bent portion 50 of the actuator 20. The lever and portion 50 are retained assembled by a hairpin retainer 53. In practice, as the thermostat 34 Warm up it winds more tightly.

To effect adjustment of the thermostat from the exterior of the housing, means are provided on the cover plate 18. As shown in FIGURES 2 and 3, this means comprises a rotatable member 54. The member 54 includes a shoulder 56 adjacent its upper end and is provided with an upper threaded end portion 58. Intermediate the threaded portion 58 and the shoulder 56 is an annular groove 66 adapted to receive an E-ring 62 which is located at the upper side of the cover plate 18. Thus, the rotatable member 54 is retained in assembled relation on the cover plate by engagement between the shoulder 56 and the E-ring 62, at opposite sides of the cover plate is. The rotatable member 54 includes a clamping nut 64 which clamps the rotatable member in adjusted position. In addition, its upper end is slotted as indicated at 66 for engagement with a screw driver to effect adjustment of the thermostat after the clamping nut 64 has been loosened.

The lower portion of the adjusting member 54 extends into the housing formed by the pocket or recess 16, and is there provided with a worm-like thread 68 which engages with the toothed periphery of the disc or sector 36. Accordingly, rotation of the member 54 results in rotation of the toothed sector or disc and since this is fixedly connected to the post 3% it results in rotational adjustment of the post with corresponding adjusrnent of the eifectiveness of the coiled bimetal thermostat 34.

Referring now to FIGURES 4 and 5 there is shown a similar construction in which like parts are identified by like reference characters. This embodiment of the invention differs from that previously described in that instead of the toothed sector or disc 36 fixed to the post 30, there is provided a plate 70 having at one side thereof a notch 72. The plate 76 thus constitutes an arm for connecting the post 30 to a rotatable member 74.

In this case the member 74 instead of being mounted for rotation only, has its upper portion threaded as indicated at 76, and this threaded portion is received in a threaded nut 78 fixed in an open-ing in the cover plate 18. A lock nut 80 and lock washer 82 are provided for locking the rotatable member 74 in adjusted position.

With the construction as described, it will be apparent 3. that after loosening the lock nut 80 the rotatable member 74"may berota'ted with corresponding vertical or axial advance. At its lowerend the member 74 is provided with a disc 84which extends into the notch 72, so that vertical movement of the member 74 results in corresponding rotational adjustmentof the plate 70.

In both-cases it will be observed that the entire con.- struction is mounted on the cover plate so that it may be pre-assembled and adjusted and inserted as a unit into the recess or pocket 16 formed in the manifold.

The drawings and the foregoing specification constitute a description of the improved automatic choke adjusting means in such full, clear, concise and'exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What I claim as my invention is:

1. Temperature responsive actuating mechanism for adjusting a movable member exterior of a housing in accordance with temperature variations within said housing, said housing having an enlarged opening, a removable cover for said opening, a bracket carried by the cover at its inner side, a post mounted on said bracket, a coiled bimetal'thermostat having its inner end fixed to said post, a U-shaped thermostat lever including laterally spaced arms at opposite sides of said thermostat rotatable at one end thereof on said post at one side of said bracket, an elongated element extending between said arms adjacent the other end of said arms, the outer end of said thermostat having a hook portion connected to said element to rotate said lever and to be guided thereby, and an elongated actuator connected to said element and extending through and movable in an opening'in said cover for transmitting motion to said movable member.

2. Temperature responsive actuating mechanism for adjusting a movable member exterior of a housing in accordance with temperature variations within said housing, said housing having an enlarged opening, a removable cover for said opening, a bracket carried by the cover at its inner side, a post mounted on said bracket, a coiled bimetal thermostat having its inner end fixed tosaid post, a U-shaped thermostat lever including laterally spaced arms at opposite sides of said thermostat rotatable at the free endsthereof on said post, an elongated element extending between said arms adjacent the other end of said arms, the outer end of said thermostat having a hook portion connected to said element to rotate said lever and to be guided thereby, and an elongated'actuator connected to'said element and extending through and movable in an opening in said cover for transmitting motion to said movable member.

3. Temperature responsive actuating mechanism for adjusting a movable member exterior of a housing in accordance with temperature variations within said housing, said housing having an enlarged opening, a removable cover for said'op'ening, a'flat bracket on the inner side of said cover, a rotarypost mounted at one end thereof'to said bracket and extending laterally therefrom, a coiled bimetal thermostat having its inner end fixed to' said post, a U-shaped thermostat lever including laterally spaced arms at opposite sides of said thermostat mounted for rotation at one end thereof on said post at one side of said bracket, an elongated actuator movable generally'longitudinally through an opening in said cover, said actuator including a laterally bent inner end portion extending between said arms adjacent the other ends of said arms, the outer end of said'thermo'stat having a portion engaging the bent inner end of said actuator to rotate said lever and to be guided in its path of movement thereby.

4. Mechanism as definedin claim 3, comprising'mean's for rotating said post to adjust said thermostat, said means comprising a rotary member having an inner adjusting portion within said housing connected to said post and an outer end portion accessible for adjustment of said post while said cover is in place.

References Cited in the file of this patent UNITED STATES PATENTS 2,123,979 'War'd July 19, 1938 2,275,742 Dillon Mar. 10, 1942 2,319,418 Lund May 18, 1943 2,564,114 Kittler Aug. 14, 1951 2,657,862 Carlson et' al Nov. 3, 1953 

1. TEMPERATURE RESPONSIVE ACTUATING MECHANISM FOR ADJUSTING A MOVABLE MEMBER EXTERIOR OF A HOUSING IN ACCORDANCE WITH TEMPERATURE VARIATIONS WITHIN SAID HOUSING, SAID HOUSING HAVING AN ENLARGED OPENING, A REMOVABLE COVER FOR SAID OPENING, A BRACKET CARRIED BY THE COVER AT ITS INNER SIDE, A POST MOUNTED ON SAID BRACKET, A COILED BIMETAL THERMOSTAT HAVING IOTS INNER END FIXED TO SAID POST, A U-SHAPED THERMOSTAT LEVER INCLUDING LATERALLY SPACED ARMS AT OPPOSITE SIDES OF SAID THERMASTAT ROTATABLE AT ONE END THEREOF ON SAID POST AT ONE SIDE OF SAID BRACKET, AN ELONGATED ELEMENT EXTENDING BETWEEN SAID ARMS ADJACENT THE OTHER END OF SAID ARMS, THE OUTER END OF SAID THERMOSTAT HAVING A HOOK PORTION CONNECTED TO SAID ELEMENT TO ROTATE SAID LEVER AND TO BE GUIDED THEREBY, AND AN ELONGATED ACTUATOR CONNECTED TO SAID ELEMENT AND EXTENDING THROUGH AND MOVABLE IN AN OPENING IN SAID COVER FOR TRANSMITTING MOTION TO SAID MOVABLE MEMBER. 